U.S. Pat. No. 4,115,956 discloses a machine tool which is in the form of a computer-numerically controllable (CNC) grinding machine. All the movement axes of this grinding machine are program-controlled simultaneous axes, in the sense that all of them may be controlled simultaneously to enable automatic fabrication of the workpiece in a programmed sequence.
The machine does enable program-controlled grinding of workpieces of arbitrary geometry. However, it has been found that programming costs for this machine frequently must be excessive in order to be able to carry out the successive machining steps--involving changes in relative position between the grinding wheel and workpiece--with sufficient precision. When machining very complex workpieces, this may render it impossible to use such tools in the NC mode.
An object of the present invention is to devise a machine tool of this general type wherein all of the workpiece surfaces can be fabricated by a program-controlled technique in a single operating cycle, with the economic efficiency of the machining process being increased.